There are many industries and applications where sharp knives are used. Applications from surgery to meat-cutting to recreational fishing all use knives with very sharp blades and equally sharp points. Each year many users accidentally slice or puncture themselves with sharp instruments either during use, during transfer from one person to another or from inadvertent misplacement of sharps in potentially dangerous locations. This is especially dangerous in the medical arena, as potentially fatal diseases can be spread through accidental contact with sharps. Emergency Rooms are battlegrounds compared to the operating rooms where quick action amongst many people are required to save lives. Sharp protection is a must and must be easy to operate. Prior art is replete with many different style of devices that act to cover sharp blades.
There are 5 main types of prior art that exists to prevent users from accidental contact with sharp blades. The 5 areas involve devices where 1) the sharp is retracted into the body of the device, 2) where the device is a disposable or single use application, where the entire sharp with the handle is not reused, 3) a device that moves in a non-linear fashion to cover the blade while it is not in use, 4) those devices which remove a detachable blade from the handle of the device, and 5) other devices that use non-traditional or devices specific sharp handles and blades and a cover that travels in a linear fashion over the sharp.
In the first arena of prior art, patents have been granted for devices mainly in the medical field. The basic premise for this group of patents is that the blade is extended from and retracted back into, the handle of the device. There is usually one handed operation of these devices, but the Shapiro U.S. Pat. No. 5,571,128 issued on Nov. 5, 1996 discloses a device that requires “rotary and longitudinal movement of the handle” to move the surgical element. That extra step of motion can be difficult if the surgeons hands are busy holding or manipulating another device. Most patents use devices that are similar in shape to existing scalpels but are machined or molded in such a manner to create a hollow in the body of the scalpel to hold serve as a chamber to store the blade while not in use. The Dillion et al U.S. Pat. No. 5,730,751 and the Cote et al U.S. Pat. No. 5,431,672 detail this style of retracting blade into the body prior art. Dillion provides for “an inoperative location within the handle” and Cote states that the blade is slid from an “intermediate position where the blade is within the handle”. Both Cote and Dillion provide for the location of the triggering mechanism to retract the blade is nearest the distal or blade end of the device. Cote discloses the triggering mechanism on the side of the handle which could disturb the surgeon as that is the natural position of the surgeons hand during use and possibly hinder the operation of the scalpel should it be used in a tight surgical location such as under the arm or in persons with layers of fat, where the scalpel is often used past the coetaneous layers of the body. Both Cote and Dillion function only with their respective blades and handles are not transferable to current scalpels in use. There are also issues present that would make the sterilization after use of these devices to be difficult if possible at all.
The second arena of prior art involves the use of single use blades and handles. There are three main styles where the either the blade is retracted into the body, a shield is produced covering the blade or there is a separable device that is used to cover the blade. In the first style, Dambal etal in U.S. Pat. No. 6,757,977 issued on Jul. 6, 2004, Haining in U.S. Pat. No. 5,330,493 issued on Jul. 19, 1994 and U.S. Pat. No. 5,556,409 issued on Sep. 17, 1996, all disclose devices where the blade is first extended for a single use and then is withdrawn into the body and some mechanism will prevent the blade from being extended in the future. Thus making this device safe for disposal after a single use. While Dambal and Haining uses a manual method, thumb power, to retract the blade, Flumene et al in U.S. Pat. No. 6,022,364 issued on Feb. 8, 2000, is “operated through an elastic returns means”. The second style involves the uses of a shield that moves over a stationery blade. Wonderley in U.S. Pat. No. 5,417,704 issued on May 23, 1995, discloses “a blade carried by the handle adjacent one end thereof and a guard movably mounted to the handle for sliding movement relative to the handle between a protective position covering the blade and a retracted position exposing the blade.” Where Wonderley discloses a manual operation to move the shield into the desired position, Pilo et al in U.S. Pat. No. 6,589,258 issued on Jul. 8, 2003 discloses the use of an “elastic return elements to bring the blade back into the retracted inoperative position”. The third style as disclosed by Williams in U.S. Pat. No. 4,735,202 issued on Apr. 5, 1988, uses a separable shield device on a round handled scalpel that is removed and remounted after use. All of styles mentioned in this section involve the use of unique surgical handles and blades which are disposed of after use. This is an expensive alternative as the majority of the cost of a normally used scalpel is in the high precision surgically ground blade. It is not economically justifiable to use this method when medical costs are escalating very rapidly.
The third arena of sharps protection involve the use of a guard that moves to cover the sharp but does so in a non-linear path or motion. Landis et al in U.S. Pat. No. 5,843,107 issued on Dec. 1, 1998 and Schneider in U.S. Pat. No. 5,250,064 issued on Oct. 5, 1993 disclose a shield that is actuated by the surgeon's thumb, whereby a protective member is lifted away from the sharp during use. This presents several issues; as the surgeon's thumb is not naturally located above the blade during or prior to use, the cover would present sight issues as it would be in the line of sight of the surgeon during use, the cover would prohibit the use of the blade subcutaneously as is required in certain surgical procedures or involving persons who are overweight and it requires that the surgeon pay attention to something other than the patient as the surgeon must be aware of holding the shield in position. Though both of these patents allow for use on existing sharps, it involves the placement of the devices next to the sharp where there exist a large chance of accidental puncture. Capewell in U.S. Pat. No. 5,478,346 issued on Dec. 26, 1995 also discloses a sharps guard but here there is “a blade guard attached to the scalpel by a frangible tether”. Capewell uses a non-standard scalpel for this application and requires the user to move their fingers next to the sharp to operate this guard. This guard also contains the problems associated with the Landis and Schneider patents as well.
The fourth arena of the prior art involves the use of devices whereby the sharp is attached to and then removed from the handle. In one group, there are those devices where the sharp is directly attached to the handle and another group contains devices where the sharp is placed into a cartridge which is then placed upon the handle. Both groups involve handling of the sharp prior to it's inclusion into some protective cover, increasing the chance of accidental puncture. In the first group, Herbert et al in U.S. Pat. No. 5,868,771 issued on Feb. 9, 1999, Newman et al in U.S. Pat. No. 6,626,925 issued on Sep. 30, 2003 and van der Westhuizen et al in U.S. Pat. No. 5,330,494 disclose the procedure of attaching the sharp to the handle and then attaching a sliding blade guard. Once the sharp is used, the blade can be removed along with the guard. Herbert uses existing style surgical handles, while van der Westhuizen and Newman use a unique handle that is modified at the distal end of the handle nearest the sharp, to receive the guard. Both devices require the use to load the sharps device onto the handle, requiring the unguarded sharp to be handled by those that the device is designed to protect, and often those people are wearing gloves which will reduce tactile feel. In a different approach disclosed by Noack in U.S. Pat. No. 5,312,429 issued on May 17, 1994, where a unique blade with an opposed tang is removed by sliding blade release element when the element is slid down the handle toward the sharp. This is a two handed operation involving two separate pieces. In the sliding of the element, if one's hand slips from the element it would be certainly by cut by the exposed blade. Also the blade is without direction or restraint when released from it's location on the handle. It could fly anywhere in the operating room as there is tension built up between the tang of the blade and the rest of the blade that was forced over the post on the handle. Another adaptation of this concept is found the series of patents from Jolly et al, U.S. Pat. Nos. 5,827,309, 5,752,968 and 5,792,162 issued Oct. 27, 1998, May 19, 1998 and Aug. 11, 1998 respectively. These Jolly patents show a blade remover which first removes the tang of the blade from the post into a notch on the sliding guard. Then '968 discloses that “guard 30 can be advanced distally to force blade 50 from blade carrier”. The built in stresses mentioned above are now increased with a forcible removal of the blade with the sliding guard, increasing the chance for the blade to misdirected about the operating room. In the second group, Gharibian in U.S. Pat. No. 5,527,329 issued on Jun. 18, 1996 and Cohn et al in U.S. Pat. No. 5,938,676 issued on Aug. 17, 1999 disclose the use of a cartridge system whereby the sharp is placed into a cartridge which is then encased by a guard prior to it's placement onto the handle. This operation is safer as the sharp is guarded during assembly but creates a situation as each discloses a unique handle designed to receive the cartridges and shields. Cohn et al in U.S. Pat. No. 5,941,892 issued on Aug. 24, 1999 combines prior art by incorporating the cartridge concept that is “removably retained within the cavity” in the handle. This is a safe alternative but uses unique handles. All of the prior art in this section requires the use of two hands to safely operate the device which is at odds with current FDA compliance rules.
In the last arena of prior art, a guard is placed around a stationery blade. There is nothing unique about the concept, and it's application can be seen from the simple to the complex. In simple application of this concept, Patent Applications US2004/0244204 to Elsner-Zehnder et al and US2002/0133952 to Kenny, disclose blade guards whereby the knife is held in place and a guard is placed onto the knife. These applications are not surgically based but neither is the invention limited to medical applications. More complex applications of the concept are found in Abidin et al in U.S. Pat. No. 5,662,669 issued on Sep. 2, 1997 and U.S. Pat. No. 5,569,281 issued on Oct. 29, 1996, Jolly et al in U.S. Pat. No. 5,741,289 issued on Apr. 21, 1998, Matwijcow in U.S. Pat. No. 5,207,696 and Dolgin et al in U.S. Pat. No. 5,071,426 issued on Dec. 10, 1991. Matwijcow discloses a rack and pinion system for movement of the guard over the blade which causes a reverse sequence of logic, as the user needs to pull back to move the guard forward. This could be confusing in the fast paced operating room where several different type of devices might be used at once. Dolgin also uses a “linkage system” to extend the blade guard “over a substantially greater distance than the distance which the surgeon's fingers move in operating the actuating mechanism”. This is unnecessarily complex and expensive concept using unique handles which requires manual loading of the blades onto the handle. Jolly provides for both linear actuation of the guard along with a rotational movement of the guard and blade away from the handle for cleaning purposes. This device is complex and expensive to manufacture and use. The Abidin '281 patent discloses a guard which “comprises an inverted U-shaped channel member telescopically mounted within the hollow handle for sliding movement therein”. It is held in position by exposed an exposed pin which would be in the way of the surgeon's hands and could be accidentally triggered to move at the improper time. This device is also not usable with currently used scalpels and it requires a unique handle. Abidin '669 is another internally guided blade guard with a unique handle. But this patent also discloses in column 10 line 11, that it does not work with conventional scalpel blades. '669 does combine a blade guard and a blade ejector, but FIG. 36 details the need for two handed operation to remove the blade. FIG. 45 and FIG. 48 show that the blade is not restrained after it is removed from the handle, and as described above, there is a considerable amount of tension on the blade. The disclosure details the added tension as the guard actually pushes the blade off of the post upon which it is attached. There is nothing to restrain the loose blade. An unrestrained blade could fly off anywhere in the operating room and this is not a safe method of removal. '669 also discloses in FIG. 32 the complicated way of attaching the blade with two small pins, which would be very difficult with gloved hands in a hurried operating room. FIG. 13D of '669 shows the user sliding the guard forward using their forefinger, which would present an obvious problem should the guard become slippery due to bodily fluids, and the users finger slips from the guard onto the exposed blade.
There is a need to preclude the problems associated with the prior art and the current state of technology in this field. It would be preferable to produce a device that would provide current users with a device that would improve upon some of the shortcomings of the prior art. It would be advantageous that the prior art would be able to produce a device that would cover sharps with a minimal of effort, with only a single hand to operate such a device, and that the device be usable over a wide range of existing sharps. Industry has set standards for their equipment and it would be desirable to have a device that fits their standard equipment, rather than adapt to new equipment. Sharps users, especially surgeons, are used to the fit, form and feel of their tools of the trade, and are reticent to change. It is well practiced in the medical field, that metal sharps handles are used because they possess a certain weight and balance that plastic handles have a hard time replicating. Industry needs to adapt protections to currently used sharps, as new device are usually meet with skepticism and doubt, and are thus not used. Industry does not want to carry duplicative inventories of many similar products because they do not work with one another.
It would be desirable for an invention that would be simple in design and yet adaptable to different types of sharps. It would be desirable to have this device be made in such a manner that it would be reusable and manufacturable in great quantities, lower product costs while assuring repetitive quality throughout the devices could even make this product disposable after a single use. It would be desirable to have the device made of autoclavable plastic or metal and designed so that it will not have any hidden recesses or other cavities that would trap harmful bacteria precluding the chance that it could be autoclavable. It would be advantageous that a blade remover apparatus be designed where only a single hand is needed for operation and where the blade is held rather than just pushed off the blade post creating a more secure environment.